DEFECT STUDIES IN A 2-DIMENSIONAL PERIODIC PHOTONIC LATTICE

Structures arranged so as to exhibit a complete photonic bandgap (PBG) have been proposed for a variety of technological applications. McCall et al. have reported an experimental and numerical investigation of microwave propagation in a two-dimensional array consisting of low-loss high-dielectric-constant cylinders. This system was shown to have a complete PBG, as well as a defect mode. Here we present an experimental investigation of the properties of a variety of defect modes, created by altering a region in the otherwise periodic lattice of dielectric cylinders. These alterations include removing one or more cylinders from the lattice in a variety of spatial separations and orientations, and also a procedure whereby the defect mode frequency may be tuned by slightly perturbing those cylinders closest to the defect region. The implication of these results for supercell numerical simulations and potential technical applications are discussed.